Normal (negative) values

A normal, or negative,
test for Lyme disease can mean one of the following:

You do not have Lyme disease. A negative PCR
test usually means that you do not have a Lyme disease infection.

You have Lyme disease but it does not show up on the test (false-negative). This is more likely with the antibody
tests than with PCR. Reasons for a false-negative result include the following:

You have not yet made antibodies to the
Lyme disease bacteria. The infection may be present, but it is too early to
find antibodies. This is most likely to occur during the first several weeks of
infection.

Blood levels of antibodies against Lyme disease bacteria
are too low for the test to detect.

Occasionally, some people who
were not treated correctly with antibiotics in the early stage of infection may
not have antibodies to the Lyme disease bacteria in later stages of the
illness.

Abnormal (positive) values

An abnormal, or
positive, test for Lyme disease can mean one of the following:

If antibodies are found, you may either have
Lyme disease now or had the illness in the past. Once you have a Lyme disease
infection, antibodies to the bacteria will usually stay in your body for the
rest of your life.

If Lyme disease bacteria DNA is found, you probably have an
active Lyme disease infection.